2020/10/29 by Chiara Sorgentone, Sorgentone, Chiara, Petia Vlahovska +1
Physics and Astronomy · #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #physics.flu-dyn
paper · pdf · doi:10.48550/arxiv.2011.00724
arXiv admin note: text overlap with arXiv:2004.05493
arxiv created 2020/12/02 · arxiv updated 2020/12/03
We study the effect of surfactant on the pairwise interactions of drops in an applied uniform DC electric field using a combination of numerical simulations based on a boundary integral formulation and an analytical theory assuming small drop deformations. The surfactant is assumed to be insoluble in the bulk-phase fluids. We show that the surfactant weakens the electrohydrodynamic flow and thus dielectrophoretic interactions play more prominent role in the dynamics of surfactant-covered drops compared to clean drops. If drop conductivity is the same as the suspending fluid, a nondiffusing surfactant can arrest the drops' relative motion thereby effectively preventing coalescence.